title: A low-molecular-weight compound K7174 represses hepcidin: possible therapeutic strategy against anemia of chronic disease.
abstract: Hepcidin is the principal iron regulatory hormone, controlling the systemic absorption and remobilization of iron from intracellular stores. The expression of the hepcidin gene, HAMP, is increased in patients with anemia of chronic disease. Previously, the synthetic compound K7174 was identified through chemical screening as a novel inhibitor of the adhesion of monocytes to cytokine-stimulated endothelial cells. K7174 also ameliorated anemia induced by inflammatory cytokines in mice, which suggests a possible involvement of hepcidin regulation. The present study was performed to assess the impact of K7174 on hepcidin expression in a human hematoma cell line and in mice in vivo. We first demonstrated that K7174 treatment in HepG2 cells significantly decreased HAMP expression. Then, we conducted microarray analysis to determine the molecular mechanism by which K7174 inhibits HAMP expression. Transcriptional profiling confirmed the downregulation of HAMP. Surprisingly, we found that K7174 strongly induced GDF15, known as a negative regulator of HAMP expression. Western blotting analysis as well as ELISA confirmed the induction of GDF15 by K7174 treatment. Furthermore, K7174-mediated HAMP suppression was rescued by the silencing of GDF15 expression. Interestingly, we found that K7174 also upregulates CEBPB. Promoter analysis and chromatin immunoprecipitation analysis revealed that CEBPB could contribute to K7174-mediated transcriptional activation of GDF15. Subsequently, we also examined whether K7174 inhibits hepcidin expression in mice. Quantitative RT-PCR analysis with liver samples from K7174-treated mice demonstrated significant upregulation of Gdf15 and downregulation of Hamp expression, as compared to control mice. Furthermore, serum hepcidin concentration was also significantly decreased in K7174-treated mice. In conclusion, K7174 inhibits hepcidin expression partly by inducing GDF15. K-7174 may be a potential therapeutic option to treat anemia of chronic disease.
authors.affiliation: Department of Hematology and Rheumatology, Tohoku University Graduate School, Sendai, Japan ; Molecular Hematology/Oncology, Tohoku University Graduate School, Sendai, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Fujiwara
authors.forename: Takashi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nagasaka
authors.forename: Yoko
authors.initials: Y
authors.lastname: Okitsu
authors.forename: Yuna
authors.initials: Y
authors.lastname: Katsuoka
authors.forename: Noriko
authors.initials: N
authors.lastname: Fukuhara
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Onishi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Ishizawa
authors.forename: Ryo
authors.initials: R
authors.lastname: Ichinohasama
authors.forename: Naohisa
authors.initials: N
authors.lastname: Tomosugi
authors.forename: Hideo
authors.initials: H
authors.lastname: Harigae
mesh_terms: D000740:Anemia / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000840:Anisoles / Q000494:pharmacology*; D001381:Azepines / Q000494:pharmacology*; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D002908:Chronic Disease / Q000188:drug therapy*; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D053263:Gene Regulatory Networks / Q000187:drug effects / Q000235:genetics; D055436:Growth Differentiation Factor 15 / Q000235:genetics / Q000378:metabolism; D006406:Hematoma / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D056945:Hep G2 Cells; D064451:Hepcidins / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D020014:K562 Cells; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D000840:Anisoles; D001381:Azepines; D022782:CCAAT-Enhancer-Binding Protein-beta; D055436:Growth Differentiation Factor 15; D064451:Hepcidins; C410337:K 7174